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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2016

Abstract

Legislation in Sweden and Norway requires that Dairy cattle have outdoor acess in summertime. Pasture utilization can be challenging with high-yielding cattle abd karge herd-sizes. Tehrefore, many farmers choose to offer their cows Access to an exercise- and recreation area only, rather than a full Production pasture. However, is an exercise paddoc as attractive as Production pasture for the cow? We compared part-time production and exercise grazing in an automated milking system, with outdoor acess in the morning (4.5 h) and the evening (4 h). The Production pasture group (P)was offered fresh Production pasture daily and given a Limited silage ration night-time. The exercise pasture group (E) was given Access to a small exercise paddoc and were fed silage ad libitum 24 hours. Milk yield dit not differ significantly: 36.1 kg for P and 36.0 kg for E. However, behaviour differed, with 5.5 (P) and 2.6 h(E) spent outdoors, and 3.7 h (P) and 0.6 h (E) grazing time. In conclusion, while milk-yields were similar between the Groups, lower ammounts of supplementary feed were needed for cows on treatment P, who also spent longer hours putdoors and grazing.

To document

Abstract

Accurate estimation of winter wheat frost kill in cold-temperate agricultural regions is limited by lack of data on soil temperature at wheat crown depth, which determines winter survival. We compared the ability of four models of differing complexity to predict observed soil temperature at 2 cm depth during two winter seasons (2013-14 and 2014-15) at Ultuna, Sweden, and at 1 cm depth at Ilseng and Ås, Norway. Predicted and observed soil temperature at 2 cm depth was then used in FROSTOL model simulations of the frost tolerance of winter wheat at Ultuna. Compared with the observed soil temperature at 2 cm depth, soil temperature was better predicted by detailed models than simpler models for both seasons at Ultuna. The LT50 (temperature at which 50 % of plants die) predictions from FROSTOL model simulations using input from the most detailed soil temperature model agreed better with LT50 FROSTOL outputs from observed soil temperature than what LT50 FROSTOL predictions using temperature from simpler models did. These results highlight the need for simpler temperature prediction tools to be further improved when used to evaluate winter wheat frost kill.